


The Lost Daughter

by ImpulsivelyFicced



Category: Percy Jackson and the Olympians - Rick Riordan, The Heroes of Olympus - Rick Riordan
Genre: Alternate Universe - Canon Divergence, F/F, F/M, Harpy Jason, M/M, Merman Percy, Role Reversal
Language: English
Status: In-Progress
Published: 2015-08-27
Updated: 2015-09-02
Packaged: 2018-04-17 13:27:51
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,979
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4668266
Author URL: https://archiveofourown.org/users/ImpulsivelyFicced/pseuds/ImpulsivelyFicced
Summary: <blockquote class="userstuff">
              <p>When Annabeth was 12, she fell off a boat. When someone brings her to shore, she begins to believe in the impossible.</p>
<p>When she is 14, Annabeth finds out her life has not been a lie, but that there is something she has been missing.</p>
            </blockquote>





	1. Prologue

**Author's Note:**

> Alternate Title: In Which Zeus Is Not As Much Of A Dick As He Could Have Been, Except He Kind Of Still Is.
> 
> Or; What if Zeus had never decreed that the gods couldn't get too involved in their kid's lives, so instead of going to Camp Half-Blood all demigods get to spend their summers with their parents, learning about their parents' spheres of influence and how to fight for their lives, if they have to.
> 
> Except Athena, because she doesn't actually have kids, right? Right?

**Prologue**

 

When Annabeth was 12 she fell off a boat. Her father was doing a research paper on aquatic warfare before World War II, and somehow the university had found the only working pre-WW2 ballast boat that still worked. Annabeth’s school had gotten out the week before, and since her stepmother got seasick and her stepbrother’s pre-K prep school didn’t get out for another week Annabeth and her father went down to Virginia Beach together. Annabeth liked spending time alone with her dad anyway. She could pretend it was still just the two of them.

 

Frederick Chase was a great scholar – that was what her mother had loved about him, he always said – but as a boater Annabeth’s father left much to be desired. She hadn’t realized that until he hit the breakwater near the pier and one bump sent Annabeth out of her seat on the bench and into Virginia Beach Bay.

 

Annabeth sank fast, caught by a current. She knew how to swim, but even after kicking off her shoes and kicking hard, Annabeth gained no ground. She kicked and fought, and sank deeper. Staying calm was Annabeth’s specialty, but when something large swam past her through the water she screamed. And lost air. Her fight was desperate now, but the shimmering circle of sunlight overhead refused to come any closer.

 

Suddenly there were arms around Annabeth’s middle, and she forced herself not to kick her rescuer in the crotch. If he had a crotch. There was something slimy and scaly against Annabeth’s bare feet, but all the air she’d lost was making her head spin. And with one kick, whoever was helping her gained more ground than Annabeth had lost. A few more seconds and they broke the surface.

 

Annabeth coughed and retched, trying to expel all the water from her lungs. She hadn’t noticed they were moving forward, she was too busy being sick. But as soon as her feet hit sand and she could stand, the arms around her were gone. When Annabeth turned, there was no one to be seen. She waded ashore and made her way back to the docks, where her father was panicking and trying to talk to the coast guard on duty at the same time.

 

She didn’t tell them the truth. Annabeth didn’t lie, but even at 12 she had started to figure out that not telling the whole truth was not the same as lying. So she told them what had happened; she’d fallen overboard but had tried to swim to the surface. Some Good Samaritan – a surfer or diver probably – had dived down to get her and helped her make it to shore, and left when they knew she was safe. Both her father and the coast guard accepted this without question, and her father had even seemed disappointed that the Good Samaritan hadn’t stuck around so he could thank them properly. Once they’d packed up and were heading back to the summerhouse, Annabeth wondered if he would feel the same if her dad knew a mermaid had saved her.


	2. Chapter 1

**Summary for the Chapter:**

> Annabeth gets a sneak peek into a world she didn't know existed.

**Chapter 1**

It’s hard to hold on to childhood belief as you grow up, and especially not once you’re a teenager. But if there was one thing Annabeth knew for certain, it was that she had been saved from drowning by a mermaid when she was 12 years old. Or a merman, since Annabeth distinctly remembered there being dark hairs on the arms around her waist. Annabeth couldn’t quite decide if she felt guilty about throwing up seawater on those arms, or not. Her father wouldn’t let her go near the docks again for the rest of the summer though, so Annabeth couldn’t go looking for him to maybe apologize. And the next summer they went camping in the Appalachians, so there was another summer lost. But when she turned 14 Annabeth told her dad she wanted to go to the beach. And to Annabeth’s surprise, her stepmother backed her up.

 

“If Annabeth isn’t afraid of the water,” Her stepmother said. “Then neither should you be.” And it was true; Annabeth wasn’t afraid of the water. She’d been practicing her swimming almost obsessively for the last 2 years. Annabeth might have wanted to meet the merman, but she had no interest in being rescued again.

 

So Frederick rented the beach house again and as soon as al three kids were out of school they moved down to Virginia Beach.

 

Annabeth waited a few days before beginning her search. One day when the whole family was down at the beach – and once her father had fallen asleep with a manuscript over his face – Annabeth set off down the beach. She figured under the pier was as good a place to start as any, since it was deep and near where she’d fallen in.

 

Finding a dry rock to sit on, Annabeth began her watch. She’d been reading about mermaids over the last two years, but she found the variety to the stories frustrating. Annabeth had finally decided her merman was one of the nicer breeds. Maybe not full blown Little Mermaid, but since he’d brought her to the surface instead of drowning her she figured he liked humans – or at least didn’t eat them. Annabeth also figured he was more mythological than scientifically possible, since there hadn’t been any fins on his arms and as far as she could remember he’d been about her size and not layered in fat. Maybe he was a Little –

 

There!

 

A pair of eyes and shock of dark, messy hair just where the water got deep. And then they were gone. A normal swimmer would have at least surfaced to take a breath, and even if they hadn’t they would have needed to resurface again. Annabeth hopped off her rock and walked right to the water’s edge. She wasn’t afraid of being pulled in. Annabeth imagined the can of mace her stepmother had given her for her 14th birthday would work just as well underwater.

 

“I know you’re there!” Annabeth called. “Are you the one that helped me to the shore when I was 12?”

 

There was no reply for a long time, and just as Annabeth was starting to feel stupid, a head surfaced again. “I don’t know,” The boy said, shaking drops of water from his black hair. “Were you 12?”

 

Annabeth grinned and folded her arms. “Yes, I was. Were you?”

 

The boy scowled. “No. My birthday is in August.”

 

Annabeth laughed. So he had been about her age. Younger. For some reason that made Annabeth feel better. The boy swam forward and the water far behind him rippled. Green scales – the same color as his eyes – showed through the water.

 

“D’you mind if we move this somewhere else?” He asked. “My stepmom won’t be happy if I drag shore mud back home.”

 

“Your…step mom?” The modern sounded weird coming from a merman.

 

He nodded distractedly. “Yeah, I’ll tell you more if we move.” The boy pointed down the beach, back towards Annabeth’s family. There’s a fishing dock a little ways down the beach, you know it?” Annabeth nodded. She’d passed it on her way to the pier. “We can hang there. Anybody that passes will just think I’m swimming and you didn’t want to get in.”

 

Hang; there was another piece of slang she hadn’t expected from him. “Okay.” Annabeth stood and dusted her shorts off. “I’ll meet you down there.” The boy smiled and disappeared under water.

 

As Annabeth walked she wondered if moving had just been his way of getting rid of her, but she saw flashes of green scales, or dark hair, or tan skin as she walked along the beach. And when Annabeth settled herself at the end of the dock and put her feet in the water, he surfaced. The boy pulled himself halfway onto the dock with his elbows and braced himself with them to stay in place on the dock.

 

“Much better.” He grinned, and Annabeth was a little annoyed at how cute he was. Fish were not cute, so why should half a fish be? “Now I can actually introduce myself. Percy Jackson, son of Sally Jackson and Poseidon, god of the sea.” Percy held out one hand.

 

Annabeth stared at him. “Poseidon? Not…not Triton?”

 

Percy snorted and rolled his eyes. “Nah, that’s my stepbrother, and he won’t be ruling anyone until dad steps down. Which you know, never gonna happen. But Triton is obsessed with reminding everyone that _he_ is dad’s heir.”

 

“Uh…okay. But you mentioned a stepmom too. And your mom…Sally?”

 

Percy grinned. “She’s human, although she has her own kind of magic according to dad. My mom and stepdad live in New York, where I’m from. Amphitrite’s my stepmom, but she’s pretty cool to me. Not all crazy like some goddesses are to their step kids. Probably cause my dad treats her really good besides the affairs thing, unlike some gods.”

 

That made sense to Annabeth in some weird way, and since Percy’s hand was still extended she took it. “Well then, its nice to meet you Percy Jackson, son of Poseidon and Sally Jackson. I’m Annabeth Chase, daughter of Frederick Chase.”

 

“And?” Percy asked, looking at her expectantly. His hand was warm, even though it had just been under water.

 

“And?”

 

“Who’s your godly parent? You’re a half-blood – a demigod – like me, aren’t you? So who’s your mom?”

 

Annabeth kicked the dock, but tried to keep the annoyance out of her voice. “I don’t know. What makes you think I’m anything?”

 

Percy shrugged. “Just feels like it. We know each other when we meet. Are you dyslexic and ADHD?”

 

Surprised and a little annoyed at the sudden change in topic, Annabeth scowled. “Yeah. What’s that got to do with anything?”

 

He shrugged again, and it was annoyingly smooth coming from him. Like he really didn’t care either way. “That’s one of the signs. You have a hard time reading regular English because your brain is hardwired for Ancient Greek. And you’re hyper cause your instincts and reflexes are geared for the battlefield, not sitting in a classroom. Dunno why you don’t know who your mom is though. Most parents will claim their kids by their 12th or 13th birthdays.”

 

Percy pushed himself up and stared hard into Annabeth’s eyes. They were so close they could have kissed, and for a brief moment Annabeth – addled by Percy’s ocean air scent and sea green eyes – thought he was going to kiss her.

 

Then he was gone and sinking back down into the water. “Nope. You don’t really look like any of the goddesses I know. Maybe my friend Grover could help but I’m not too good at it.”

 

Annabeth opened her mouth to say something – although she really wasn’t sure what – when she felt footsteps approaching on the dock and heard someone saying her name. Annabeth turned to see her dad headed towards them. Annabeth turned bkc to Percy, worried he would vanish into the water. But he seemed perfectly unconcerned, and since everything that was showing looked perfectly human, Annabeth decided not to worry if Percy wasn’t.

 

When Annabeth’s dad reached them, he put one hand on Annabeth’s shoulder. “Honey? Its time to head back to the house to get cleaned up for dinner.” He glanced at Percy, and Percy held out a hand.

 

“My name’s Percy Jackson. Nice to meet you Mr. Chase.”

 

Annabeth’s dad took the proffered hand and she noticed he seemed rather impressed with Percy’s strong grip. “Nice to meet you too Percy. Do you know each other from school?”

 

Percy shook his head before Annabeth even needed to think up a lie. “Nope, I’m from New York. We just met today.” He glanced at the sun over his shoulder. “I should be going anyways. My brother Tyson will be wondering where I am.” Percy looked back at Annabeth. “See you back here tomorrow, about one?” He asked.

 

Annabeth grinned. “Sure. See you tomorrow seaweed brain.”

 

Percy waved and slipped all the way into the water, careful to swim off down the beach like a normal person until he was out of sight.

 

Annabeth stood and walked back to the start of the dock with her dad.

 

“He was a handsome young man.” Her stepmother commented with a straight face, and Annabeth was so surprised, she laughed.

**Notes for the Chapter:**

> ITS NOT LONG ENOUGH
> 
> Oh well.
> 
> I know this is starting slow, and the next chapter is mostly recap of the universe, but chapter 3 gets more interesting I promise!


	3. Chapter 2

**Summary for the Chapter:**

> Annabeth has questions, and Percy likes to talk a lot.

**Notes for the Chapter:**

> Longer chapter (thank the gods) but its mostly just a lot of dialogue that explains what's different about this world vs the original PJO/HoO world. I literally just finished the series less than a month ago so its all still fresh in my brain. If its still fresh in yours you might find the recap a little obnoxious, but there is stuff that's changed so read it if you want? I don't know. I'm just glad to be able to post this.

**Chapter 2**

Annabeth was almost late to her meeting with Percy. Her stepmother had insisted on doing Annabeth’s long blonde hair into a French braid down her back. It was more complicated than Annabeth could or would have done herself, but she liked the way it kept her curls out of her eyes. When she got to the docks, Percy was waiting. His eyes were blue today, since a bank of clouds had moved over the bay and the water to an icy steel. But he greeted her with a huge smile.

 

“Where’d seaweed brain come from?” Percy asked after they’d exchanged greetings.

 

Annabeth shrugged. “I don’t know, it just sounded right in my head. Why? Don’t like it?”

 

“My godly cousins and the rest of the uh…family I guess, they like to call my dad seaweed beard. Something about old rites sailors used to do in his name when they crossed the meridian?”

 

“I think I read a book somewhere that mentioned that.” Annabeth admitted. “Why’d you hesitate over family?” She asked.

 

“Could you ever get used to being related to almost every god, creature, or hero in the ancient myths? Bad enough I’m named after one.”

 

Annabeth thought about the cursory research she’d done on her laptop the night before, and shuddered. “Yeah, good point. But what about your mom’s side?”

 

Percy shook his head. “Nope. Mom’s an only child, and her parents died in a plane crash when I was a baby. Which now I know about everything is pretty spiteful and morbid.”

 

“And you’ve lost me.” Annabeth said.

 

“Zeus. Well, all the gods at some point or other, but Zeus in particular. Mr. Spiteful himself.” The sky gave a half-hearted rumble of thunder, but Percy ignored it. “He didn’t like it when my dad and mom got together, and gods and mortals can’t really _not_ have kids. So when mom found out she was pregnant he couldn’t take it out on her since that might start a fight with my dad. So he killed her parents instead. Now me, my mom, and even my stepdad won’t risk flying just in case, since the air is straight up Zeus’ territory. Well, I can fly on a Pegasus but that’s only cause the first Pegasus is my brother.”

 

Annabeth’s head was spinning, yet it all still felt right to her. Or at least true. Then again, Percy did have a tail. And it would be pretty hard to make any of this up anyway. “Why would Zeus care if your dad had a kid?” She asked.

 

“He doesn’t when Poseidon has a non human kid. But…” Percy looked a little bashful. “Demigods – that’s us half-bloods, half mortal half god – tend to be pretty powerful. And especially kids of the Big Three: Zeus, Poseidon, and Hades. I can breath under water and control it; the sea or any freshwater so long as the local god or naiad is willing. I can even make a little typhoon around myself. My friends Jason and Thalia can summon lightning, fly, and control storms. They’re Zeus’ kids. Well Thalia is. Technically Jason’s dad is Jupiter, but same difference. Nico, Bianca, and Hazel are Hades or Pluto’s kids, and they can summon and sort of control the dead, travel anywhere by shadow, and Hazel can summon cursed precious metals and gems from the earth. She mostly uses that power to feed her horse Arion though, who is _also_ my brother.” Percy took a deep breath and grinned at Annabeth’s slack jawed amazement. “I told you it was complicated. And that’s just Big Three spawn.”

 

“And you think I’m a demigod?” Annabeth asked, feeling a little disappointed. “I’ve never done anything like that.”

 

Percy shrugged. “I don’t think you’re a demigod.” He grinned up at her. “I _know_ you’re one of us.” Annabeth smiled back and Percy went on. “A lot of kids aren’t super powered freaks like me either. Other than being able to read ancient Greek and fight most kids are just…normal. Or if they do have powers its always related to their parent’s sphere of influence. Plus a lot of mortal parents don’t know that they were with gods. Jason’s girlfriend Piper is a daughter of Aphrodite, but her movie star dad had no idea when they were together, and still doesn’t. She’s got this freaky Charm Speak power too, but for Aphrodite kids its kinda rare. Only one of Piper’s sisters can do it besides her. But a lot of kids have no special ability attached to being their mom or dad’s kids. You’re just…good at something in particular. Something your parents like or control. Like my friends Connor and Travis Stoll. Their dad is Hermes, god of messengers and thieves and like everything else that didn’t already have a god. No special powers, unless you call being able to steal the web from under a spider and being superbly annoying a super power.”

 

Annabeth tried to think of anything she was really good at. Her dad always said she was a smart as her mother was, but surely all the goddesses were smart. And none of her teachers would use the word smart to describe Annabeth – not with the dyslexia and ADHD anyway. Stubborn maybe, but not smart. And certainly not wise, like her dad’s nickname for her. His little Wise Girl. Annabeth shook her head and kicked some water up with her foot. “Whatever you say Percy.” She glanced over at him, and another question pooper into her head and off her tongue. “Are all of Poseidon’s kids born mer-people? Is that where mermaids come from?”

 

Percy stared at her for a long moment, his brows furrowed. “You think I’m a – Oh!” Percy’s tail slapped the water so hard Annabeth winced in sympathy, and he hurriedly pulled the tail under again. “Nah. No way Annabeth, I’m as human as you are. I bleed red and everything. Nah, I just look like this during the summer.”

 

“Like a werewolf during the full moon? Are you a werefish?” She asked, and this time Annabeth slapped a hand over her mouth. “Sorry,” She said from behind closed fingers.

 

Percy scowled at her. “Yup, you’re definitely one of us.” He teased, mock serious.

 

Well that got Annabeth over her embarrassment, and she kicked water at him. “And just what’s that supposed to mean seaweed brain?”

 

Percy achieved a much larger wave with the help of his tail, which Annabeth thought was totally unfair. “It means you just can’t keep from asking questions, even if they might be rude. Everyone knows that demigods are at least half suicidal. Its how we know we’re on the right path.”

 

Annabeth laughed, and since she was already suitably soaked she decided to let it go. “Alright fine, I concede. Now answer my question seaweed brain. Why do you look like a merman if you aren’t one?”

 

“I don’t actually recall that being your question.” Percy began, and laughed when Annabeth raised a warning foot. “Okay, okay! See, when demigods reach a certain age we tart to smell really good to monsters. All the ones from the old myths are still around, by the way. We’re okay in school, because the smell of all the other kids and teachers and staff disguise our smell. But when summer comes, we’re kind of like beacons. Imagine a big blinking neon sign above my head reading, “Come eat me please!” So to keep us all from being eaten and to teach us about our very dangerous lives, our godly parents invite their kids to spend the summer with them. Most kids just serve as handmaidens or messengers or charioteers, but for me, Jason, and Thalia that means getting turned into a merman and a pair of harpies, respectively.”  Percy let his tail rise to the surface for a brief moment. “We don’t _have to_ , but it makes life in the water and in the sky way easier. And most monsters aren’t stupid enough to attack us in our parent’s home turf. And if one is or we get caught on an excursion or quest well,” Percy shrugged. “That’s what we train for.”

 

“I…guess that makes sense?” Annabeth said. “As much as anything else you’ve told me does anyway. How many gods have you met?”

 

“A few,” Percy said. “There are actually a few hundred gods. But I’ve met the ones everyone knows. Hermes, Aphrodite, the twins Artemis and Apollo. Met Aries once, didn’t much like him. I’m more a fan of Mars, even if both annoy me. Been down to the Underworld more times than I’d like to remember too, but I’ve only seen Hades once or twice. He’s kind of a recluse. Also in serious need of a nap.”

 

“How can you talk like that about the gods? Won’t they smite you or something?” Annabeth asked, more out of curiosity than awe.

 

“Well sure, any of them _could_ smite me.” Percy admitted. “But to be honest I think its too much effort to smite That One Annoying Kid.”

 

Annabeth laughed. “That title really suits you.”

 

“Doesn’t it just?” Percy laughed and pulled himself up higher on the dock. “Speaking of being annoying.” He reached down below the water and fished around for a moment. “I told my dad about you last night. He said you could be any number of goddesses kids.” He blushed a little, but before Annabeth could ask Percy made noise that sounded very much like ‘success’. He pulled out two polished, perfectly round stones and held them out to her. “But he did give me these. Since you’re not officially claimed he doesn’t think and Iris Message will work – “

 

“Iris Message?”

 

“Basically Skype for the gods. Anyway, dad gave me these instead. He says they’ll stay in place so just-” Percy pressed them into Annabeth’s hand. “Leave the white one on the end of the dock when you leave, and the blue one while you’re here. If I get here before you do,” He produced a third, green pebble. “I’ll leave this one. That way we’ll know when we’re both around. I’m with my dad all summer, but I’m not allowed to come up by the shore everyday.”

 

“Okay.” Annabeth turned the stones in her hand. “They were warm, like Percy’s skin, and she couldn’t stop thinking about how he’d blushed. She placed the blue stone on the edge of the dock. Even though it moved when she prodded it, something about the stone felt permanent too. And if you couldn’t trust a god, whom could you trust?

 

“Sounds good. And here I was thinking I’d have to remember you by the sound of your voice. “Annabeth grinned at the sour expression on Percy’s face.

 

“That story is all wrong I hope you know,” He said. “According to my dad and Nico anyway.”

 

“Yeah whatever seaweed brain. Now you mentioned brothers. Two horses, Triton, and…Tyson? Tell me about him.”

 

“Oh man, Tyson’s the best!”

 

And so they passed the day that way. As little as Percy’s family was on his mom’s side, his dad’s side was just that big. Not even counting the gods. Percy asked about Annabeth’s family too, and she told him about her dad’s work, her stepfamily, and why she’d fallen into the water in the first place. But Annabeth wondered about her mom’s side of the family, and just how many siblings she really had.

**Notes for the Chapter:**

> Next chapter is when it gets into Annabeth's own problems and Athena and stuff, so be ready! its written, I just have to write ch 4 before I can post 3. And I'm a little out of practice at writing straight couples and I'm really wary of the "if you have to make them kiss to let people know they're interested in each other, you're doing it wrong" rule, so if anything is sounding too forced to you let me know!

**Author's Note:**

> I've got more chapters than I'm posting today, but I'm trying to keep myself going by rewarding myself with posting chapters, so hopefully I'll actually be able to finish something for once.
> 
> Although nothing seems to come out even half as long as it looks on paper...


End file.
